Boat anchors of various types have been known since antiquity and man has constantly sought to improve the efficiency of anchors and to make them more practical. A major advance in the art took place when the Danforth anchor came into being. The Danforth anchor has the flukes pivoted in relation to the shank and may also include crown elements or plates positioned rigidly on the fluke structure. The Danforth anchor, as well as others of the same general type, can be made much lighter than traditional types while still maintaining deep penetrating ability due to the construction and geometry of the anchor. Anchors of the Danforth type have found great utility in connection with smaller boats used for fishing and/or recreation.
A recognized attribute of all pivoted fluke anchors and particularly those possessing crown elements is that the anchors are non-fouling in comparison to rigid traditional types and much more easily retrievable when fouled on the bottom. The development of loop or pocket shanks has increased the retrievability of pivoted fluke anchors still further in the recent prior art.
The below-listed prior U.S. Pat. Nos. are made of record herein under 37 C.F.R. 1.56:
2,249,546 PA1 2,487,549 PA1 2,490,423 PA1 2,563,380 PA1 2,641,215 PA1 2,894,474 PA1 3,024,756 PA1 3,026,840 PA1 3,030,907 PA1 3,269,348 PA1 3,430,596 PA1 3,557,739 PA1 3,964,420
While the devices in these known prior patents include some features common to the present invention and bear a broad similarity to the invention, nevertheless, no known prior art anchor possesses the combined abilities of the invention including greater compactness, easier separation of parts for storage in a smaller space, and, most importantly, a substantial improvement in the ability of the anchor to resist fouling under a variety of situations which may arise when the anchor is on the bottom. This improved anti-fouling ability is derived principally as a result of the provision on opposite sides of the flukes of pairs of independently free-swinging crown plates whose pivot or swing axes are coaxial with the pivot axis of the flukes relative to the shank of the anchor. This arrangement, coupled with an increased swing arc for the crown plates and positive stop means to limit the swinging movement of the crown plates, has added greatly to the overall operational efficiency of the anchor in a manner not heretofore known or attainable in the prior art.